What is Dag & how does it work?

It's a copy of the decentralized blockchain coin history. It's required for local mining. DAG stands for Directed Acyclic Graph, the technique used for store the data. DAG stands for Directed Acyclic Graph.

How does blockchain work?

Blockchain works by grouping transactions together. Each individual transaction is approved by miners one at a time and placed in the block. Once a block is full the block is attached to the end of the chain. The chain is the ledger that keeps track of the all the transactions on the network.

Which cryptocurrencies use only Dag?

All of the cryptos listed above use only DAG except Dero. Dero uses a hybrid system of both blockchain and DAG. As a result it has the best of both worlds. That is to say it is highly secure and has great inbuilt economic incentives from blockchain mining. On the other hand the DAG part of the network makes it run efficiently.

How do DAG-based Ledger nodes reach consensus faster than blockchain networks?

DAG-based ledger nodes reach consensus significantly faster than blockchain networks. For example, Hedera uses a gossip protocol that transmits data at lightning-fast speeds. When a node receives new information, it immediately shares it with another node. The two nodes each choose another node randomly and transmit the newly learned information.